Networking Security

Linux and Windows support for network security and protocols are comparable. Both enable support for IPSec, an open standard for cryptography-based protection at the IP layer. IPSec verifies the identity of a host or end point and ascertains that no modifications were made to the data during transit across the network and encrypts data. OpenSSH, OpenSSL, and OpenLDAP are available on Linux and corresponding closed source implementations -- SSH, SSL, LDAP -- are available on Microsoft systems. 

Linux is somewhat superior due to continuing security issues with Microsoft IIS and Exchange/Outlook. Apache and Postfix are cross-platform applications and tend to be more secure than corresponding Microsoft products. Application security for Linux is also enhanced with firewalling built into the kernel. And Snort is an excellent intrusion detection system. 

One notable recent addition the Linux kernel for x86-based systems is Ingo Molnar's exec-shield, which provides protection against attacks from buffer or function pointer overflows and against other types of exploits that rely on overwriting data structures and/or putting code into those structures. The exec-shield patch also makes it more difficult to conduct a shell-code exploit. Since exec-shield operates transparently applications do not need to be recompiled. 

Microsoft is taking strides to redesign the security of its products and provides patches for its installed base. Still, security issues in legacy Windows products persist and complicate this task. This leaves many Microsoft users exposed to security threats since patches must be well documented prior to deployment. 

Also, the tendency for Microsoft to mix data and program code in its applications, e.g., Active X, can allow untrusted data from outside the system and can cause the activation of arbitrary code with untrusted data.